STM32H753 vs STM32H743: Can I substitute?

[PMath.4]

I need to get some PCBs made by JLC but they are continually out of stock of the STM32H743IIT6 which is my target processor. They do however have the STM32H753IIT6. Is there any reason I can't substitute these to run identical firmware?

Thanks

[Tesla DeLorean]

Basically same die, with HASH/CRYP units enabled. Watch your import/export docs and requirements.

[PMath.4]

Clive thanks for the confirmation.

Do you know if it has the same chip id? I use HAL_GetREVID (DBGMCU->IDCODE) to distinguish between 400 and 480MHz parts

 if(HAL_GetREVID()==0x1003)__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
 else __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

Thanks

peter

[Tesla DeLorean]

Yes, die and stepping information should be consistent.

ST has particularly poor management of SKUs held by distributors and segregation of new vs old steppings.

The H753 have fewer FLASH size options (amount tested), and the H750 will likely also work in a pinch.

You might be able to determine CRYP via the Unique ID bits, or by probing the peripheral

[waclawek.jan]

Isn't that documented in the RM?

 

JW

[PMath.4]

"Isn't that documented in the RM?"

Yes if you know where to look and can find it - thanks

Unfortunately the H750 doesn't have enough flash for my applications -see here for details. Quite pleased with myself on this one :)

[Tesla DeLorean]

>>Unfortunately the H750 doesn't have enough flash for my applications

Same die, it's on there..

[PMath.4]

"Same die, it's on there.."

You mean that if I use a binary for the H743 on a H750 it might magically find the extra flash? How about programming it? The program is over 512Kbytes long

[waclawek.jan]

It's the same with all 0-ending "value line" models across all STM32 families: they are the same dies as the "full featured" ones, except portions of them (memories, some peripherals) are not tested and testing is performed under relaxed conditions (e.g. smaller temperature range).

It does not mean you should rely on the extra flash on the 'H750 - certainly not for a commercial product - and also ST may any time decide to lock the "unavailable" portions through some internal mechanism, or if there's enough demand, they may even generate the needed masksets for optimized parts which genuinely don't have those portions.

JW